The subject matter disclosed herein relates generally to medical imaging systems, more specifically to radiation detectors for ionizing radiation, such as X-Ray and Gamma Rays and even more particularly to identifying sub-pixel locations for events.
In nuclear medicine (NM) imaging, such as single photon emission computed tomography (SPECT) or positron emission tomography (PET) imaging, radiopharmaceuticals are administered internally to a patient. Detectors (e.g., gamma cameras), typically installed on a gantry, capture the radiation emitted by the radiopharmaceuticals and this information is used, by a computer, to form images. The NM images primarily show physiological function of, for example, the patient or a portion of the patient being imaged.
The detectors may include an array of pixelated anodes. Improved resolution may be obtained by determining sub-pixel locations of events. Generally, in order to obtain a sub-pixel position of an event inside a pixel, non-collecting signals of the event at the 4 pixels immediately adjacent to the pixel within which the event occurs may be used. However, for a pixel located at a sidewall, there are only 3 pixels immediately adjacent to the pixel, and for a pixel located at a corner, there are only 2 pixels immediately adjacent to the pixel, resulting in incomplete information for sub-pixel location determination.